Nests for storage, stacks for freezing. Dishwasher safe. www.goodcook.com. Warranty: 100% satisfaction guarantee. This product is warranted to be free from defects, unless damaged by misuse. If it fails to meet your complete satisfaction, please return it with proof of purchase to the address below and we will gladly replace it for free or send you an equivalent item. This warranty does not affect your statutory rights.